print("hello wolrd")


import numpy as np
import matplotlib.pyplot as plt


def f(x):
    return x**3 - 2 * x - 5


a = np.array([1, 2, 3])

b = f(a)

print(b)


# 用plt画函数f(x)的图像
x = np.linspace(-10, 10, 1000)
y = f(x)
plt.plot(x, y)

# 显示图像
plt.show()
